Leblanc



Jan. 31, 1956 G. LEBLANC 2,733,423

SELECTOR OR MIXER DEVICES FOR POLYCHROMATIC ILLUMINATION Filed March 23,1953 2 Sheets-Sheet l i m A Jan. 31, 1956 G. LEBLANC 2,733,428

SELECTOR OR MIXER DEVICES FOR POLYCHROMATIC ILLUMINATION Filed March 23,1953 2 Sheets-Sheet 2 5 4 2 f I "LU, 1, 42222222 5&5 25 2/ g i Ix A? i 65 L Q:\ i

United States Patent SELECTOR OR MIXER DEVICES FOR POLY- CHROMATICILLUMINATION Georges Leblanc, Paris, France, assignor to CompagnieGenerale de Travaux dEclairage et de Force, Anciens EtablissementsClemancon, Paris, France, a French society Application March 23, 1953,Serial No. 344,117 Claims priority, application France March 24, 1952Claims. (Cl. 340-335) This invention relates to so-calledchromo-selector devices of the kind in which the light from a pluralityof sources of illumination of different color may be combined or mixedin selected proportions in order to obtain a desired total color efiect,as for theatrical, advertizing, or any other purposes.

It is an object of the invention to provide a light-selector or mixer ofthe type specified, which is simple, compact and efiicient. Anotherobject is to provide improved selector means for selecting the preciseproportion in which the light emanating from a plurality of sources ofdilferently colored light is mixed so as to produce any desired colorshade for the resulting illumination. A further object is to providesuch means wherein selection of the desired illumination is effected byactuation of a single selector member regardless of the number ofindividual light sources used. A further object is to provide suchselector means in the form of a compact control panel or box and tofacilitate the selection of the desired shade of illumination by theprovision of indexing means cooperating with a movable selector pointer.

Further objects may appear as the description proceeds.

In a preferred form of embodiment, my improved selector device maycomprise, in combination with a plurality of light sources of differentcolor and power supply circuits therefor, resistances interposed in saidcircuits, a conductive member movable in engagement with all and any ofsaid resistances to short circuit an amount of each resistance variablewith the position of said member, and a selector knob for varying theposition of said member.

The preferred embodiment of the invention will now be described by wayof illustration but not of limitation with reference to the accompanyingdrawings, wherein:

Fig. 1 is an overhead view of the selector-box;

Fig. 2 is a horizontal view section on line II-II of Fig. 3;

Fig. 3 is a vertical section on line III-III of Fig. 2;

Fig. 4 is a detail perspective view of the control member;

Fig. 5 is a diagram of the circuitry.

As shown, a casing 1 is provided, which may have se cured to its top, asat 2, any suitable diagram or pattern providing the operator with ameans of selecting the desired shade of illumination. One example of adiagram suitable for this purpose is the standard colorimetric diagramdrawn up by the International Committee for Illumination. Moregenerally, any indexing pattern may be used providing qualitativeindications, of a nature adequate to guide the operator in the selectionof the desired color shade. For example, such indications may includedescriptions of the nature, characteristics, or merely designations ofthe apparatus units which are to cooperate in producing the effectindexed in each of a plurality of areas of the diagram, for instance inthe case of advertizing panels. Quantitative indications may also beused, such as indications of the numerical proportions between thedegrees of energization of the various units of equipment used. Oragain, a spatial diagram may be used, such 'ice as one indicating thecoordinates of the remote equipment to be controlled.

A control member or knob 3 having an index or pointer 4 secured to it,is mounted for parallel displacement in all directions over thecasing 1. As shown in Figs. 3 and 4, the knob 3 is connected by avertical rod 5 extend ing through a wide aperture 6 (Figs. 1 and 3) inthe casing top, with a part 7 within the casing. Secured to the part 7is a cross member 8 adapted for displacement, through interposed bearingballs such as 9, over horizontal plates 10 fixed in the casing.

Secured to the bottom side of the part 7 is a horizontal insulatingplate 11 to the under side of which a horizontal rectangular frame 12made of conductive material is secured. The frame 12 engages resistancewires 13. The resistance wires 13 are wound on supports 14 resilientlymounted on the bottom of easing 1 through spring mounts 15.

The resistor supports 14 are disposed in a manner to be presentlydescribed.

A first pair of parallel spaced links 16 (Fig. 2) have their one endspivoted to spaced point-s 18 of the fixed casing structure, and theirother ends pivoted to diametrically opposed points of a horizontal disc19 movable in a horizontal plane. A further pair of parallel links 17have their one ends pivoted to diametrically opposed points of the disc19, spaced degrees from the pivotal points of the links 16 on said disc,and their other ends pivoted to correspondingly spaced points of theaforementioned part 7 secured to the control knob. The pairs of links16, 16 and 17, 17 define a pair of cooperating parallel linkage systemswhereby the frame 12 can have any desired parallel displacement impartedto it in its plane or" movement, by actuation of the knob 3.

As shown in the exemplary embodiment described, four elementary lightsources are used, provided by the lamps 21, which may emit yellow, red,green and blue light respectively. In this case, there are provided forresistor elements 13, arranged along the four arms of a cross, Withtheir inner ends spaced from one another, as clearly shown in Figs. 2and 5. The outer end 13a of each resistor winding 13 is connected to oneterminal of a corresponding one of the lamps 21. The other terminals ofthe lamps are connected in parallel over a common lead 22 to one side ofan A.-C. supply source. The other side of the supply source connects bya lead 23 with the conductive rectangular slide frame 12.

In operation, it will be apparent that on suitable manipulation of thecontrol knob 3, any desired position may be imparted to the slider 12within the range allowed by the parallel linkage systems 16, 17. Thecomponents are so dimensioned that the slider 12 can be positioned toshort-circuit completely any selected one of the resistors 13, or toshort selected complementary amounts of the lengths of the respectivefour resistors.

It will be understood that many modifications may be made in the typicalembodiment described and shown, without exceeding the scope of theensuing claims. Thus, the resistance elements, instead of being woundelements as shown, might be provided in the form of strips or the like.The circuit connections between the light sources and the power supplyand including said resistances may ditfer from the simple circuithooleup shown. For example, the resistances instead of acting directlyon the energizing circuits for the light sources, may act thereonindirectly as through the intermediacy of appropriate relays, electronic amplifiers, or similar expedients which will be ob vious to thosefamiliar with the art. Means may be provided whereby the elector memberor knob may be used, simultaneously with or separatly from its action inmodifying the relative intensities of the light sources, also to adjustthe total intensity of the resulting light.

What I claim is:

1. In a device of the kind described, in combination with a plurality ofelectric light sources of difierent colors and a power supply therefor,a casing, elongated resistors mounted in said casing in angularequispaced relation in the same plane and each having the outer endthereof connected to one terminal of a respective one of said lightsources, a conductive rectangular member displaceable in contact withall said resistors and parallel thereto and connected to one side ofsaid power supply, conductor means connecting the other side of saidsupply to another terminal of each light source, a selector knoboperable from outside the casing and operatively connected to saidmember, and parallel linkage means operably connected with said memberto constrain the motion thereof whereby actuation of the knob willimpart a parallel displacement to said member for determining therelative amounts of said resistors effectively connected to each lightsource.

2. 1m a device of the kind described, in combination with a plurality oflight sources of different colors and a power supply therefor, a casing,elongated resistors mounted'in said casing in angular equispacedrelation in the same plane and each having the outer end thereofconnected to one terminal of a respective light source, a conductiverectangular member displaceable in contact with all said resistors andparallel thereto and connected to one side of said supply, conductormeans connecting the other side of said supply to another terminal ofeach light source, a selector knob connected to said member and actuablefrom outside the casing, an intermediate element, a first pair ofparallel links having their one ends pivoted to the casing and theirother ends to said intermediate element, and a second pair of parallellinks having their one ends pivoted to said element and their other endsto said member, whereby said member is constrained to a paralleldisplacement in any direction in engagement with said resistors onactuation of said selector knob.

3. In a device of the kind described, a plurality of light sources ofdifferent colors, a power supply therefor, circuit means interconnectingsaid supply to each of said light sources and including elongatedresistors arranged in angularly equispaced relation in the same planeand respectively connected with said light sources, a common conductivemember displaceable in engagement with all of said resistors andparallel thereto to vary the relative amounts thereof efiectivelyconnected with said light sources and hence the relative illuminatingintensities of said light sources, means constraining said member toparallel displacement in any direction in engagement with saidresistors, and actuating means to displace said memher.

4. in a device of the kind described, a plurality of light sources ofdifferent colors, a power supply therefor, circuit means interconnectingsaid supply to each light source and including elongated resistorsarranged in angularly equispaced relation in the same plane andrespectively connected with said light sources, a conductive memberdisplaceable in engagement with all said resistors and parallel theretoto vary the relative amounts thereof effectively connected with saidsources and hence the relative illuminating intensities of said sources,a first pair of parallel links having their one ends pivoted to fixedpoints, an intermediate element having the other ends of said firstlinks pivoted thereto, a second pair of pivoted links having their oneends pivoted to said element and their other ends pivoted to said memberwhereby said member is constrained to parallel displacement in anydirection in engagement with said resistors, and a selector knob foractuating said member.

5. In a device as claimed in claim 4, resilient mounting means for saidresistors to provide resilient pressure contact between the resistorsand said member during displacement of said member.

References Cited in the file of this patent UNITED STATES PATENTS1,976,005 Boden Oct. 9, 1934 2,265,980 Berger Dec. 16, 194-1 FOREIGNPATENTS 449.656 Germany Sept. 20, 1927

